I operate a J170D and have my loading graphs downloaded onto Avplan and have had the parameters checked against my POH figures.
I check that the C of G is within the envelope at tkof, ZFW, and landing before tkof.
If the C of G remains within the envelope at all stages of flight, then i am safe and legal.
It doesnt matter to me if the Cof G moves close the the fore or aft limits, just that it stays wholly within the envelope.
You can do the same with a J230 without having to worry about bags of concrete.
Just load the aircraft within limits and if your calcs show too far fwd or aft, then adjust by reducing fuel, baggage, or both.
Very easy to do without complex mathematics, and the 2 EFB providers make it a breeze!